JP7300353B2 - Die bonding apparatus and semiconductor device manufacturing method - Google Patents

Description

The present disclosure relates to a die bonding apparatus, and is applicable to, for example, a die bonder having a function of applying paste adhesive.

As part of the manufacturing process of semiconductor devices, there is a process of mounting semiconductor chips (hereinafter simply referred to as dies) on wiring boards, lead frames, etc. (metal, organic substrates such as glass, epoxy, etc.) and assembling packages. Part of the process includes a process of dividing a semiconductor wafer (hereinafter simply referred to as a wafer) into dies (a dicing process) and a bonding process of mounting the divided dies on a substrate. A semiconductor manufacturing apparatus used in the bonding process is a die bonder.

A die bonder is a device that bonds (mounts and adheres) a die onto a substrate or an already bonded die using resin paste, solder, gold plating, or the like as a bonding material. For example, in a die bonder that bonds a die to the surface of a substrate, a suction nozzle called a collet is used to pick up the die by suction from the wafer, convey it onto the substrate, apply a pressing force, and heat the bonding material. By doing so, the operation (work) of performing bonding is performed repeatedly.

When resin is used as a bonding material, resin paste such as Ag epoxy and acrylic is used as an adhesive (hereinafter referred to as paste adhesive). A paste-like adhesive that adheres the die to a lead frame or the like is encapsulated in a syringe, and the syringe. It moves up and down with respect to the lead frame to inject and apply the paste adhesive. That is, a predetermined amount of paste adhesive is applied to a predetermined position by a syringe filled with the paste adhesive, and the die is crimped and baked onto the paste adhesive to be bonded. A recognition camera is attached to the vicinity of the syringe, and the recognition camera confirms whether the applied paste-like adhesive is applied in a predetermined shape and in a predetermined amount at a predetermined position.

JP 2013-197277 A

In order to improve the adhesion of a mold resin that seals a die mounted on a substrate such as a lead frame, which is a metal frame, to the substrate, the substrate is subjected to satin finishing. However, after the paste adhesive is applied, the paste adhesive spreads due to the fine irregularities formed on the substrate, and the applied paste adhesive changes its shape. This makes it difficult to inspect the applied paste adhesive.
An object of the present disclosure is to provide a technique that enables visual inspection of a paste-like adhesive that changes in shape after application.
Other problems and novel features will become apparent from the description of the specification and the accompanying drawings.

A brief outline of a representative one of the present disclosure is as follows.
That is, in the registration operation before mass production, the die bonder measures the time from the operation of applying the paste adhesive to the metal frame during mass production to the operation of capturing an image of the paste adhesive, and applies the paste adhesive to the metal frame. After waiting for the measured time after application, the paste adhesive applied to the metal frame is imaged to obtain a reference inspection image.

According to the die bonding apparatus, it is possible to inspect the appearance of a paste-like adhesive that changes in shape after being applied.

It is a figure explaining application|coating of a paste adhesive. FIG. 4 is a diagram for explaining problems in applying a paste-like adhesive to a lead frame that has undergone a satin finish; FIG. 4 is a diagram for explaining problems in applying a paste-like adhesive to a lead frame that has undergone a satin finish; BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the outline|summary of embodiment. It is a figure explaining the test|inspection method of the paste adhesive in 1st embodiment. It is a figure explaining the test|inspection method of the paste adhesive in 1st embodiment. It is a figure explaining the test|inspection method of the paste adhesive in a 1st modification. It is a figure explaining the test|inspection method of the paste adhesive in 2nd embodiment. It is a figure explaining the test|inspection method of the paste adhesive in 2nd embodiment. It is a figure explaining the test|inspection method of the paste adhesive in 2nd embodiment. It is a figure explaining an example of the prediction method of a shape. It is a figure explaining the test|inspection method of the paste adhesive in a 2nd modification. It is a figure explaining the test|inspection method of the paste adhesive in 3rd embodiment. 1 is a conceptual diagram of a die bonder of an embodiment viewed from above; FIG. 15 is a configuration diagram of an optical system of the die bonder of FIG. 14; FIG. 15 is a block diagram showing a schematic configuration of a control system of the die bonder of FIG. 14; FIG. It is a flow chart which shows a manufacturing method of a semiconductor device.

Embodiments, modified examples, and examples will be described below with reference to the drawings. However, in the following description, the same components may be denoted by the same reference numerals, and repeated descriptions may be omitted. In addition, in order to make the description clearer, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the actual embodiment, but this is only an example, and the interpretation of the present invention is not intended. It is not limited.

First, the application of the paste adhesive will be described with reference to FIG. FIG. 1(a) is a diagram showing a photographed image of a paste-like adhesive applied on a tab of a lead frame in which tabs are arranged in a grid pattern, and FIG. 1(b) is a binary image of FIG. 1(a). FIG. 4 is a diagram showing a converted image;

The application of the paste-like adhesive to the lead frame, which is a metal frame, is performed, for example, in a preform section provided in front of the bonding section. First, the preform unit uses a recognition camera to position the lead frame LF to which the paste adhesive is to be applied. Positioning is performed by pattern matching or the like as in the case of the bonding head. Next, the preform part is injected from a nozzle at the tip of a syringe in which the paste adhesive PA is enclosed, and is applied along the trajectory of the nozzle. The syringe is driven on the XYZ axes according to the shape to be applied, and the trajectory of the syringe draws a free trajectory such as an X mark shape or a cross shape to apply the liquid. Finally, the preform section inspects the state of the pasty adhesive PA after application using a recognition camera (appearance inspection is performed). The presence or absence of the paste adhesive PA, application area, application shape (shortage, protrusion), etc. are inspected as necessary. The inspection is performed by a method of counting the number of pixels after separating the paste area by the binarization process shown in FIG. In the following description, it is assumed that the application pattern of the paste-like adhesive PA is in the shape of an X mark.

As shown in FIG. 1(a), depending on the state of application of the paste adhesive, there are insufficient (middle of FIG. 1(a)), overrunning (lower of FIG. 1(a)), and the like. The upper part of FIG. 1(a) shows a case where the paste adhesive is applied normally.

In order to improve adhesion with the mold resin that seals the lead frame as a substrate to which the die is bonded, the lead frame is subjected to satin finishing. Problems occurring when a paste adhesive is applied to a satin-finished lead frame will be described with reference to FIGS. 2 and 3. FIG. FIG. 2(a) is a view showing a photographed image immediately after the paste adhesive is applied to the surface of the lead frame that has undergone the satin finish, and FIG. 2(b) is a state after a predetermined time has passed from FIG. 2(a). 2(c) is a conceptual cross-sectional view taken along line AA of FIG. 2(b), and FIG. 2(d) is a binarized image of FIG. 2(a). 2(e) is a diagram showing the binarized image of FIG. 2(b). FIG. 3 is a view showing a photographed image of a paste-like adhesive applied on tabs of a lead frame in which tabs are arranged in a grid pattern.

When the paste adhesive PA is applied to the tab TB serving as the die mounting portion of the lead frame LF to which the satin finish is applied, the paste adhesive PA becomes thinner over time as shown in FIGS. blur. The surface of the lead frame LF that has undergone the satin finish is not flat, but has fine irregularities. The applied paste-like adhesive PA spreads so as to soak into the irregularities. In this specification, this bleeding is referred to as bleed BO. In the early stage, the bleed BO thinly spreads in a uniform direction with the passage of time. Even if the lead frame is not satin-finished and the viscosity of the paste adhesive is low, the paste adhesive spreads over time.

When the appearance inspection is performed immediately after applying the paste adhesive PA, the inspection is finished before the bleed BO spreads. However, if for some reason re-inspection or inspection after a predetermined time has elapsed, it is necessary to consider the change in bleed BO.
Bleeding includes oozing out of the solvent and oozing out of the paste itself. In the case of exudation of the paste itself, it is judged to be defective when there is a change in the bleed BO. In this case, it can be detected from the binarized image of FIG. 2(e) after a predetermined time has passed since the application and the binarized image of FIG. 2(d) immediately after the application which has been registered in advance.

On the other hand, the bleed BO hardly affects the amount of the paste adhesive PA applied. When an appearance inspection is performed using an image captured by a recognition camera installed above the paste-like adhesive PA, even if an attempt is made to measure the amount of the paste-like adhesive PA, the paste amount ( area/coating shape) cannot be detected. If the captured image is binarized as it is, as shown in FIG. The current inspection system, which can only do so, determines that there is too much coating.

A case where an inspection is required after a predetermined time has elapsed since the application of the paste adhesive PA will be described with reference to FIG.

In FIG. 3, the paste adhesive PA is applied sequentially downward from the upper right tab of the lead frame LF in which the tabs are arranged in a grid pattern, and after the paste adhesive PAR is applied to the lower right tab, from the right The paste adhesive PA is applied sequentially downward from the top position of the second row, and then applied to the third and fourth rows in the same manner. Therefore, the paste adhesive PAS applied to the uppermost tab in the first row has the longest elapsed time after application, and the paste adhesive PAE applied to the bottom tab in the fourth row has the longest elapsed time after application. become smaller.

As shown in FIG. 3, when the paste adhesive applied to all four rows of tabs was visually inspected after application of the paste adhesive PAE after application of the four rows, as shown in FIG. The spread of BO is different for each tab. Since the visual inspection of the paste adhesive is usually performed for each row, the spread of the bleed BO on the tab paste adhesive applied first in the row and the paste adhesive applied last on the tab are different from each other. different for each.

When all tabs are inspected after application to multiple tabs such as one row or multiple rows, the time from application to inspection differs for each tab, the spread of bleed BO differs for each tab, and the inspection results vary depending on the tab. It changes depending on the position.

Next, an outline of an embodiment for solving the above problems will be described with reference to FIG. FIG. 4(a) is a view showing a captured image immediately after the paste adhesive is applied to the surface of the lead frame, and FIG. 4(b) shows a captured image after a predetermined time has passed from FIG. 4(a). 4(c) is a diagram showing the binarized image of FIG. 4(a), FIG. 4(d) is a diagram showing the binarized image of FIG. 4(b), and FIG. (e) is a diagram showing the binarized image of FIG. 4(a), and FIG. 4(f) is a diagram showing the binarized image from which the bleeding change is removed from FIG. 4(b).

In the first embodiment, the registration timing of the reference inspection image that serves as a reference is matched with the inspection timing in the continuous operation during mass production, and inspection determination is performed by image recognition including bleeding, as shown in FIG. 4(d). On the other hand, in the second embodiment, the original coating amount (shape) is predicted from the spread of bleeding, and as shown in FIG. In the third embodiment, the inspection determination is performed by separating the bleed from the paste portion by illumination. Each inspection method will be described in detail below.

(First embodiment)
A method for inspecting a paste adhesive according to the first embodiment will be described with reference to FIGS. FIG. 5 is a flow chart for explaining a method of obtaining a reference inspection image. FIG. 6(a) is a view showing a captured image immediately after the paste adhesive is applied to the surface of the lead frame, and FIG. 6(b) shows a captured image after A minutes have passed from FIG. 6(a). FIG. 6(c) is a diagram showing a captured image after B minutes have elapsed from FIG. 6(a), and FIG. 6(d) is a diagram showing a binarized image of FIG. 6(a). 6(e) is a diagram showing the binarized image of FIG. 6(b), and FIG. 6(f) is a diagram showing the binarized image of FIG. 6(c).

As described above, in the first embodiment, the registration timing of the reference inspection image that serves as the standard is matched with the inspection timing during mass production, and inspection determination is performed by image recognition including bleeding. The inspection method described below is performed by a control device provided in the die bonder controlling a recognition camera or the like as an imaging device.

First, the registration (image acquisition) operation will be described at actual recognition timing.
(Step S1: Acquisition of Mass Production Conditions (Recognition Timing))
In actuality, no application is performed, but an idle operation is performed (step S11), and the timing (time) from application in continuous operation during mass production to appearance inspection (recognition) taken by the recognition camera is measured (step S12). As described with reference to FIG. 3, after the paste adhesive PA is applied to the plurality of tabs TB of the lead frame LF, the first applied paste adhesive PAS to the last applied paste adhesive PAE are sequentially applied. In the case of visual inspection, the time from application to visual inspection is measured. Thereby, the appearance inspection timing at the time of mass production is acquired.

(Step S2: Acquisition of reference inspection image)
The paste adhesive PA is actually applied once to the tab TB of the lead frame LF as the first substrate, and the settings such as lighting are determined (step S21). Measurement of the elapsed time is started at the same time as the application. Wait until the measured elapsed time reaches the time (actual measurement time) measured in step S12 (step S22). A reference inspection image of the agent PA is acquired, stored in a storage device provided in the control device, and registered (step S23). For example, if the time measured in step S12 is A minutes, the captured image of FIG. 6B is registered as the reference inspection image, and if the time measured in step S12 is B minutes, the image of FIG. The captured image is registered as a reference inspection image. If there is one time measured in step S11, one inspection image is acquired, and if there are multiple times measured in step S11, multiple reference inspection images are acquired for each time. As a result, a reference inspection image is acquired at the appearance inspection timing during mass production.

During mass production, inspection and judgment are performed in continuous operation. After applying the paste adhesive PA to the tab TB of the lead frame LF as the second substrate, an image is acquired using the recognition camera in the appearance inspection, and the application is normalized by comparing with the reference inspection image registered in step S23. determine whether the For example, if the captured image of the appearance inspection at the time of mass production is binarized and the time measured in step S12 is A minutes, the time measured in step S12 is compared with the binarized image shown in FIG. If it is B minutes, it is compared with the binarized image shown in FIG. 6(f).

In the first embodiment, since the recognition registration timing takes into account the change in the two-dimensional shape of the paste adhesive, it is possible to distinguish between the initial application amount and the change over time, and the registration of the reference inspection image and the appearance during mass production. Accurate inspection determination is possible by matching the acquisition timing of the inspection image in the inspection. That is, the registration timing of the reference inspection image and the acquisition timing of the inspection image during mass production (continuous operation) are matched to detect the shape change of the applied paste-like adhesive. As a result, it is possible to stabilize the determination of the presence or absence of an abnormality in the applied paste-like adhesive and to make a correct inspection determination. In addition, by automating the registration timing of the reference inspection image (apparatus is adjusted to mass production conditions), it becomes possible to eliminate differences due to operators, and it is possible to improve the operating rate.

Some representative modifications of the embodiment and other embodiments are illustrated below. In the following description of modified examples and other embodiments, the same reference numerals as in the above-described embodiment can be used for parts having the same configuration and function as those described in the above-described embodiment. shall be For the description of this part, the description in the above-described embodiment can be used as appropriate within a technically consistent range. Also, part of the above-described embodiments, and all or part of multiple modifications and other embodiments can be applied in combination as appropriate within a technically consistent range.

(first modification)
A change over time after application of the paste adhesive PA may be detected. A method of obtaining a reference inspection image in a modified example (first modified example) of the first embodiment will be described with reference to FIG. FIG. 7 is a flow chart for explaining a method of obtaining a reference inspection image.

After step S2 in FIG. 5, the recognition camera is used to acquire a reference inspection image of the paste adhesive PA applied to the tab TB of the lead frame LF as the first substrate, and the elapsed time of acquisition of the reference inspection image is Acquire (step S24). Based on the previously acquired reference inspection image and the latest reference inspection image, it is determined whether or not the bleed spread is saturated (step S25). Steps S24 and S25 are repeated to acquire the saturation time at which the spread of bleeding is saturated (step S26).

That is, the reference inspection image is acquired a plurality of times, for example, as shown in FIGS. These reference inspection images are used to confirm changes over time and confirm saturation time. If the inspection is not performed after the application and before the apparatus is stopped, the time from the application to the inspection after the apparatus is restarted (here, referred to as the apparatus stop time) is used to determine when mass production is restarted. If the device stop time is within the saturation time, the reference inspection image corresponding to the device stop time is used for determination. If the device stop time is longer than the saturation time, the reference inspection image corresponding to the saturation time is used for determination.

(Second embodiment)
A paste adhesive inspection method according to the second embodiment will be described with reference to FIGS. 8 to 11. FIG. FIG. 8 is a flow chart for explaining registration of spread of bleed. FIG. 9 is a flow chart for explaining the appearance inspection at the start of construction. FIG. 10 is a diagram for explaining prediction of the amount (shape) of paste adhesive applied immediately after application. FIG. 10(a) is a view showing a captured image immediately after the paste adhesive is applied to the surface of the lead frame, and FIG. 10(b) shows a captured image after A minutes have passed from FIG. 10(a). FIG. 10(c) is a diagram showing a captured image in a state where B minutes have passed since FIG. 10(a). FIG. 10(d) is a diagram showing a captured image after A minutes have elapsed from FIG. 10(a), and FIG. 10(e) is a diagram showing a binarized image of FIG. (f) is a binarized image calculated immediately after application from the binarized image of FIG. 10(d). FIG. 10(g) is a diagram showing a captured image after B minutes have elapsed from FIG. 10(a), and FIG. 10(h) is a diagram showing a binarized image of FIG. 10(g). (i) is a binarized image calculated immediately after application from the binarized image of FIG. 10(h). FIG. 11 is a diagram illustrating an example of a shape prediction method.

As described above, in the second embodiment, the original coating amount (shape) is predicted from the spread of the lead, and inspection determination is performed after eliminating the change in bleeding. A detailed description will be given below.

As shown in FIG. 8, by performing a copying operation (registration operation), the speed at which bleed spreads for each product type is investigated and compiled into a database. The copying operation will be described below.

The lead frame LF as the first substrate is conveyed to the place where the paste adhesive PA is applied (step S31), and the illumination value is determined (step S32). Next, the paste adhesive PA is applied to the tab TB of the lead frame LF as the first substrate, and at the same time, measurement of elapsed time is started (step S33). Immediately after application, the recognition camera is used to capture an image of the paste-like adhesive PA, and at the same time, a time stamp is obtained (step S34). at least one of (step S35). Thereafter, steps S34 and S35 are repeated at predetermined time intervals until the spread of bleeding is saturated.

In the continuous operation at the start of construction, as shown in FIG. 9, the lead frame LF as the second substrate is conveyed to the place where the paste adhesive PA is applied (step S41), and the paste adhesive PA is applied as the second substrate. is applied to the tab TB of the lead frame LF (step S42). At the same time as the paste adhesive PA is applied, measurement of elapsed time is started (step S43). After the application, the recognition camera is used to take an image of the paste adhesive PA at a predetermined timing, and the time stamp is acquired at the same time as the image is captured (step S44).

Based on the elapsed time calculated from the time stamp acquired in step S44 and the image acquired during the copying operation, the area and shape of the area of the paste adhesive PA immediately after application are predicted (step S45). At this time, the image acquired in step S44 is inspected by normal image processing. For example, when the elapsed time from application is A minutes, as shown in FIG. Based on the amount of shrinkage, shrinkage processing is performed, and the area and shape immediately after application are calculated. As a result, a predicted image at the time of application shown in FIG. When the elapsed time from application is B minutes, as shown in FIG. Based on the amount, shrinkage processing is performed, and the area and shape immediately after application are calculated. As a result, a predicted image at the time of coating shown in FIG. 10(i) is generated, and the amount of coating at the time of coating is predicted as a result.

A simple image expansion process or image contraction process may be used as a shape prediction method. The number of contractions and the number of expansions with respect to the elapsed time are determined from the data acquired during the scanning operation. Image expansion processing or image contraction processing is performed in eight directions or four directions. As shown in FIG. 11, a starting point is provided at each inflection point (● mark) of the cross-shaped penlight trajectory, and the amount of change per time in the outward direction with respect to the contour line indicated by the arrow during the tracing operation is obtained. You may calculate using it at the time of prediction calculation. Only the area may be used to predict the amount of change.

Inspection and determination are performed based on the area and shape predicted in step S45 and the area and shape in the image immediately after application during the copying operation (step S45). For example, the inspection is performed by comparing the predicted area or shape of the application area of the paste adhesive PA with the stored application shape that serves as a reference during the copying operation. The area of the coating area is extracted by counting pixels with a specific brightness (extraction from histogram data, etc.), or using blob detection or the like. For comparison of the shape of the application area, reference data with which data after binarization can be compared is obtained by scanning operation and held, and comparison is performed by processing the difference between the reference data and the expected shape data.

In the inspection method of the second embodiment, it is assumed that the speed and direction in which the bleed spreads within a certain period of time after application are reproduced according to the previously confirmed and determined calculation formula. Therefore, the upper limit time for which the bleed continues to spread uniformly is also measured in advance by the scanning operation, and processing for invalidating the measurement result after the elapse of the upper limit time is also performed.

In the second embodiment, since the bleeding advances by a certain amount within a certain period of time, it is possible to check the application state of the paste except for the bleeding portion.

(Second modification)
A method for inspecting a paste adhesive in a modified example (second modified example) of the second embodiment will be described with reference to FIGS. FIG. 12 is a flow chart for explaining the appearance inspection at the start of construction.

The paste adhesive inspection method in the second modified example compares an image or shape captured at each elapsed time during the copying operation with an image or shape acquired at the start of mass production. This is the same as steps S41 to S44 at the time of copying operation and start of construction in the second embodiment.

During the copying operation, captured images or shape data are held for each elapsed time after the paste adhesive PA is applied to the tab TB of the lead frame LF as the first substrate (steps S34 and S35). In the continuous operation at the start of construction, the elapsed time from the application of the paste adhesive PA to the tab TB of the lead frame LF as the second substrate to the inspection is measured (step S43). Based on the value of the elapsed time, which image during the scanning operation is to be compared is selected. That is, the image or shape data during the scanning operation corresponding to the elapsed time is acquired (step S45a). Inspection and determination are performed based on the image acquired in step S44 or shape data based thereon and the image or shape data acquired in step S45a (step S46a).

(Third embodiment)
In the second embodiment, the original coating amount (shape) is predicted from the spread of the bleed, and the change in bleed is removed for inspection determination. In the third embodiment, the bleed is separated from the paste portion by illumination. A method for inspecting a paste-like adhesive according to the third embodiment will be described with reference to FIG. FIG. 13 is a diagram showing an imaging device and a lighting device in the third embodiment.

As shown in FIG. 2(c), since the paste part PST and the bleed BO are three-dimensionally different, the bleed BO is separated as dark and the paste part PST as bright. Bleed BO appears darker than the substrate surface in most cases after application (similar to the situation in which concrete appears dark after it rains). Therefore, when difference processing is performed on the image before application and the image after application, the bleed BO always appears dark (negative image). Therefore, the bleed BO portion can be excluded by performing differential processing in the mode of rounding down negative numbers. However, the paste part PST is not always bright. This is a property of liquid surface reflection, and if collimated light is applied by epi-illumination, the peripheral portion of the paste portion PST may become dark. Therefore, as shown in FIG. 13, oblique illumination (preferably ring or square type) is used together so that the peripheral portion of the paste portion PST is always bright.

As shown in FIG. 13, the illumination device ID in the third embodiment includes coaxial illumination CL and oblique illumination OL, which are epi-illumination. A coaxial illumination CL is composed of an illumination LS and a half mirror HM, and irradiates light along the optical axis of the imaging device CAM. The oblique illumination OL irradiates light obliquely with respect to the optical axis. Since the application area of the paste adhesive PA is a liquid surface, specular reflection occurs due to lighting, and bright lines and dark areas are generated according to the position of the lighting. For example, in an image acquired by oblique illumination OL, a bright line appears around the application area and a dark portion appears in the center of the application area. This is because the incident direction of the illumination is low in the oblique illumination OL. On the other hand, in the image acquired by the coaxial illumination CL, a bright line appears in the center of the coating area and a dark portion appears around the coating area. This is because the incident direction of the illumination is high in the coaxial illumination CL. A dark portion can be removed by using both the coaxial illumination CL and the oblique illumination OL.

A configuration of a die bonder as a die bonding apparatus of the embodiment will be described with reference to FIGS. 14 to 16. FIG. FIG. 14 is a conceptual diagram of the die bonder of the embodiment viewed from above. FIG. 15 is a configuration diagram of the optical system of the die bonder of FIG. 16 is a block diagram showing a schematic configuration of the control system of the die bonder of FIG. 14. FIG.

The die bonder 10 is roughly divided into a wafer supply section 1 , a work supply/transfer section 2 and a die bonding section 3 .

The wafer supply section 1 has a wafer cassette lifter 11 and a pickup device 12 . The wafer cassette lifter 11 has a wafer cassette (not shown) filled with wafer rings 16 and sequentially supplies the wafer rings 16 to the pickup device 12 . The pickup device 12 moves the wafer ring 16 and pushes up the die D so that the desired die D can be picked up from the wafer ring 16 .

The work supply/conveyance unit 2 has a stack loader 21, a frame feeder 22, and an unloader 23, and conveys the lead frame LF (see FIG. 15) in the arrow direction. The stack loader 21 supplies the lead frame LF to which the die D is attached to the frame feeder 22 . The frame feeder 22 conveys the lead frame LF to the unloader 23 via two processing positions on the frame feeder 22 . The unloader 23 stores the transported lead frame LF.

The die bonding section 3 has a preform section (paste application unit) 31 and a bonding head section 32 . The preform portion 31 applies a paste adhesive PA such as an epoxy resin to the lead frame LF conveyed by the frame feeder 22 with a syringe 36 (see FIG. 15). The syringe 36 is filled with a paste adhesive PA, and the paste adhesive PA is pushed out from the tip of the nozzle and applied to the lead frame LF by air pressure. When the lead frame LF is, for example, a multiple lead frame in which a plurality of unit lead frames are arranged in a row and connected in series, the paste adhesive PA is applied to each tab of the unit lead frame. . Here, the lead frame LF is satin-finished. The bonding head unit 32 picks up the die D from the pickup device 12 and moves the die D to a bonding point on the frame feeder 22 . Then, the bonding head unit 32 lowers the die D at the bonding point and bonds the die D onto the lead frame LF coated with the paste adhesive PA.

The bonding head unit 32 has a ZY drive shaft 60 that moves the bonding head 35 up and down in the Z-axis direction (height direction) and moves it in the Y-axis direction, and an X drive shaft 70 that moves it in the X-axis direction. The ZY drive shaft 60 is arranged in the Y-axis direction indicated by the arrow C, that is, the Y drive shaft 40 that reciprocates the bonding head 35 between the pickup position in the pickup device 12 and the bonding point, and the die D that is picked up from the wafer 14 or and a Z drive shaft 50 that is raised and lowered for bonding to the lead frame LF. The X drive shaft 70 moves the entire ZY drive shaft 60 in the X direction, which is the direction in which the lead frame LF is conveyed.

As shown in FIG. 15, the optical system 88 includes an adhesive recognition camera 33 as an imaging device for grasping the application position of the syringe 36, etc., and the bonding position where the bonding head 35 is bonded to the transported lead frame LF. and a wafer recognition camera 15 for grasping the pickup position of the die D picked up from the wafer 14 by the bonding head 35 . Each recognition camera takes an image using a lighting device that illuminates the object. A die D diced in a mesh pattern on the wafer 14 is fixed to a dicing tape 17 fixed to a wafer ring 16 .

With this configuration, the paste adhesive PA is applied to an accurate position by the syringe 36, and the die D is reliably picked up by the bonding head 35 and bonded to an accurate position on the lead frame LF.

As shown in FIG. 16, the control system 80 includes a control device 8, a driving section 86, a signal section 87, and an optical system 88. As shown in FIG. The control device 8 is roughly divided into a control/arithmetic device 81 mainly composed of a CPU (Central Processor Unit), a storage device 82 , an input/output device 83 , a bus line 84 , and a power source section 85 . The storage device 82 includes a main storage device 82a comprising a RAM storing processing programs and the like, and an auxiliary storage device 82b comprising an HDD storing control data and image data required for control. and The input/output device 83 includes a monitor 83a for displaying device status, information, etc., a touch panel 83b for inputting operator's instructions, a mouse 83c for operating the monitor, and an image capturing device 83d for capturing image data from the optical system 88. and have Further, the input/output device 83 includes a motor control device 83e for controlling a drive unit 86 such as an XY table (not shown) of the wafer supply unit 1 and ZY drive shafts of the bonding head table, various sensor signals, an illumination device, and the like. and an I/O signal control device 83f for taking in or controlling a signal from a signal section 87 such as a switch. Optical system 88 includes wafer recognition camera 15 , adhesive recognition camera 33 , and substrate recognition camera 34 . The control/arithmetic unit 81 takes in necessary data via a bus line 84, performs arithmetic operations, and controls the bonding head 35 and the like, and sends information to the monitor 83a and the like.

The control device 8 stores the image data captured by the optical system 88 in the storage device 82 via the image capturing device 83d. Using software programmed based on the stored image data, the controller/arithmetic unit 81 is used to position the die D and the lead frame LF, inspect the coating pattern of the paste adhesive PA, and inspect the surface of the die D and the lead frame LF. conduct. Based on the positions of the die D and the lead frame LF calculated by the control/arithmetic unit 81, the software drives the drive unit 86 via the motor control unit 83e. By this process, the die D is positioned on the wafer 14 and driven by the wafer supply section 1 and the driving section of the die bonding section 3 to bond the die D onto the lead frame LF. The recognition cameras used in optics 88 are grayscale, color, etc., and quantify the light intensity.

Next, a method for manufacturing a semiconductor device using the die bonder according to the embodiment will be described with reference to FIG. FIG. 17 is a flow chart showing a method of manufacturing a semiconductor device.

(Step S51: Wafer/substrate loading step)
The wafer ring 16 holding the dicing tape 17 to which the die D separated from the wafer 14 is attached is stored in a wafer cassette (not shown) and loaded into the die bonder 10 . The control device 8 supplies the wafer ring 16 from the wafer cassette filled with the wafer ring 16 to the wafer supply section 1 . Also, a lead frame LF is prepared and carried into the die bonder 10 . The control device 8 supplies the lead frame LF from the stack loader 21 to the frame feeder 22 .

(Step S52: Pick-up process)
The control device 8 causes the pickup device 12 to move the wafer ring 16 and push up the die D so that the desired die D can be picked up from the wafer ring 16, and the peeled die D is picked up from the wafer 14 by the bonding head 35. do.

(Step S53: bonding process)
The control device 8 acquires an image of the surface of the lead frame LF before application by the adhesive recognition camera 33 and confirms the surface to be applied with the paste adhesive PA. If there is no problem with the surface to be applied, the controller 8 applies the paste adhesive PA from the syringe 36 to the lead frame LF transported by the frame feeder 22 . When the lead frame LF is a multiple lead frame, the paste adhesive PA is applied to all the tabs. The control device 8 determines whether the paste adhesive PA is applied correctly after application by the adhesive recognition method according to any one of the first, second, and third embodiments and their modifications. The camera 33 confirms again and inspects the applied paste adhesive PA. If there is no problem with the application, the controller 8 bonds the die D picked up by the bonding head 35 to the lead frame LF coated with the paste adhesive PA.

(Step S54: substrate unloading step)
The control device 8 supplies the lead frame LF to which the die D is bonded by the frame feeder 22 to the unloader 23 . The lead frame LF is unloaded from the die bonder 10 .

The invention made by the present inventors has been specifically described above based on the embodiments, modifications, and examples, but the invention is not limited to the above embodiments, modifications, and examples, and various Needless to say, it can be changed.

For example, in the first embodiment, an example in which no application is actually performed in step S11 and an idle operation is performed has been described, but application may actually be performed in step S11.

Further, in the second embodiment, a copy operation (registration operation) is performed to investigate the spread speed of bleed for each type and create a database. A plurality of recognition cameras may be installed at intervals, and the spreading speed of bleed for each type may be calculated from inspection images of the paste applied to passing lead frames and the conveying speed of the lead frames, and compiled into a database. In addition, since the status during mass production can be checked continuously, it is possible to automatically correct the database and detect abnormalities and changes in paste application using data deviation.

Further, in the embodiment, an example has been described in which the die D picked up from the wafer 14 by the bonding head 35 is bonded to the lead frame LF. Alternatively, the die D picked up from the die D may be placed on the intermediate stage, and the bonding head 35 may pick up the die D again from the intermediate stage and bond it to the transported lead frame LF.

8: Control device 10: Die bonder (die bonding device)
33: Adhesive recognition camera (imaging device)
35: bonding head D: die LF: lead frame (substrate)
PA: Paste adhesive

Claims (13)

an imaging device for imaging the paste-like adhesive applied on the substrate;
a bonding head for mounting a die on the substrate coated with the paste adhesive;
a control device that performs a visual inspection based on the image of the paste adhesive imaged by the imaging device;
with
The control device is
In the registration operation before mass production,
Measuring the time from the operation of applying the paste adhesive to the substrate in continuous operation during mass production to the operation of imaging the paste adhesive with the imaging device,
Waiting for the measured time after applying the first paste adhesive to the first substrate, imaging the first paste adhesive applied to the first substrate with the imaging device, and continuous operation at the time of mass production A die bonding apparatus configured to acquire a reference inspection image as a comparison target for the image acquired in the visual inspection in the above . The die bonding apparatus of claim 1,
The control device is
In a continuous operation during mass production, the image of the second paste adhesive applied to the second substrate is imaged by the imaging device when the measured time elapses after the second paste adhesive is applied to the second substrate. to acquire an inspection image,
A die bonding apparatus configured to perform a visual inspection based on the inspection image and the reference inspection image. In the die bonding apparatus of claim 2,
The control device is
In the registration operation, a die configured to acquire a plurality of reference inspection images by imaging the first paste adhesive a plurality of times with the imaging device over time after the application of the first paste adhesive. bonding equipment. an imaging device for imaging the paste-like adhesive applied on the substrate;
a bonding head for mounting a die on the substrate coated with the paste adhesive;
a control device that performs a visual inspection based on the image of the paste adhesive imaged by the imaging device;
with
The control device is
measuring the elapsed time after applying the first paste adhesive to the first substrate,
capturing the first paste adhesive multiple times with the imaging device to obtain a plurality of images and an elapsed time during the capturing of each of the plurality of images;
measuring the area or shape of the first paste-like adhesive at the elapsed time of each image based on each of the plurality of images;
During mass production,
Measure the elapsed time after applying the second paste adhesive to the second substrate,
obtaining an inspection image and a second elapsed time during imaging of the inspection image by imaging the second paste adhesive with the imaging device;
calculating the expected area or expected shape at the time of application of the second paste-like adhesive based on the area or shape of the first paste-like adhesive at the second elapsed time and the elapsed time at the time of imaging;
A die bonding apparatus configured to perform a visual inspection based on the expected area or the expected shape. an imaging device for imaging the paste-like adhesive applied on the substrate;
a bonding head for mounting a die on the substrate coated with the paste adhesive;
a control device that performs a visual inspection based on the image of the paste adhesive imaged by the imaging device;
with
The control device is
measuring the elapsed time after applying the first paste adhesive to the first substrate,
obtaining a plurality of images or a plurality of shape data based on the plurality of images by imaging the first paste adhesive a plurality of times with the imaging device, and the elapsed time when each of the plurality of images is captured; Acquired,
In continuous operation during mass production,
Measure the elapsed time after applying the second paste adhesive to the second substrate,
Acquiring an inspection image or second shape data based on the inspection image by imaging the second paste adhesive with the imaging device, and acquiring a second elapsed time at the time of imaging the inspection image,
An image or shape data corresponding to the second elapsed time is selected from the plurality of acquired images or the plurality of shape data, and the appearance is determined based on the selected image or shape data and the inspection image or the second shape data. A die bonding apparatus configured to perform inspection. In the die bonding apparatus of claim 2,
A die bonding apparatus configured to compare the inspection image and the reference inspection image in the visual inspection to determine whether or not coating has been performed normally. The die bonding apparatus according to any one of claims 1 to 6, further comprising:
a wafer ring holder holding the dicing tape to which the die is attached;
a syringe for applying the paste adhesive onto the substrate;
A die bonding device comprising: An imaging device for imaging a paste adhesive applied on a substrate, a bonding head for mounting a die on the substrate coated with the paste adhesive, and the paste adhesion imaged by the imaging device. and a control device that performs a visual inspection based on the image of the adhesive, wherein the control device performs the imaging from the operation of applying the paste adhesive to the substrate in the continuous operation during mass production in the registration operation before mass production. The time from the application of the first paste adhesive to the first substrate until the operation of imaging the paste adhesive with the device is measured, and after waiting for the measured time from the application of the first paste adhesive to the first substrate, the second paste adhesive is applied to the first substrate. (1) loading the second substrate into the die bonding apparatus in which the image of the pasty adhesive is imaged by the imaging device and a reference inspection image is acquired as a comparison target for the image acquired in the appearance inspection in the continuous operation at the time of mass production;
applying a second paste adhesive onto the second substrate;
When the measured time elapses after the application of the second paste-like adhesive to the second substrate, an inspection image is obtained by imaging the second paste-like adhesive applied to the second substrate with the imaging device. an inspection step of performing a visual inspection based on the inspection image and the reference inspection image;
A method of manufacturing a semiconductor device comprising: In the method of manufacturing a semiconductor device according to claim 8,
In the registration operation, the control device acquires a plurality of reference inspection images by imaging the first paste adhesive a plurality of times with the imaging device as time elapses after the application of the first paste adhesive. A method of manufacturing a semiconductor device. An imaging device for imaging a paste adhesive applied on a substrate, a bonding head for mounting a die on the substrate coated with the paste adhesive, and the paste adhesion imaged by the imaging device. and a control device that performs a visual inspection based on the image of the adhesive, wherein the control device measures the elapsed time after the first paste adhesive is applied to the first substrate, and the imaging device measures the second adhesive. one paste adhesive is imaged a plurality of times to obtain a plurality of images and an elapsed time during the imaging of each of the plurality of images; a step of loading the second substrate into a die bonding apparatus in which the area or shape of the pasty adhesive is measured;
applying a second paste adhesive onto the second substrate;
Elapsed time after the application of the second paste adhesive to the second substrate is measured, and an inspection image is captured by imaging the second paste adhesive with the imaging device, and a first time when the inspection image is captured. Second elapsed time is obtained, and the expected area or expected shape at the time of application of the second paste adhesive is calculated based on the area or shape of the first paste adhesive at the second elapsed time and the elapsed time at the time of imaging. calculating and performing a visual inspection based on the expected area or the expected shape;
A method of manufacturing a semiconductor device comprising: An imaging device for imaging a paste adhesive applied on a substrate, a bonding head for mounting a die on the substrate coated with the paste adhesive, and the paste adhesion imaged by the imaging device. and a control device that performs a visual inspection based on the image of the adhesive, wherein the control device measures the elapsed time after the first paste adhesive is applied to the first substrate, and the imaging device measures the second adhesive. A die bonding apparatus that acquires a plurality of images or a plurality of shape data based on the plurality of images by imaging one paste adhesive a plurality of times, and acquires the elapsed time during the imaging of each of the plurality of images , including the step of loading the second substrate,
In continuous operation during mass production,
applying a second paste adhesive onto the second substrate;
Elapsed time after applying the second paste adhesive to the second substrate is measured, and an inspection image is obtained by imaging the second paste adhesive with the imaging device, or a second inspection image based on the inspection image is obtained. Acquiring shape data, acquiring a second elapsed time when the inspection image was captured, and obtaining a reference inspection image or shape data corresponding to the second elapsed time from the acquired plurality of images or the plurality of shape data. selecting and performing a visual inspection based on the selected image or shape data and the inspection image or the second shape data;
A method of manufacturing a semiconductor device comprising: In the method of manufacturing a semiconductor device according to claim 8,
In the inspection step, the inspection image and the reference inspection image are compared to determine whether or not the coating has been performed normally. The method for manufacturing a semiconductor device according to any one of claims 8 to 12, further comprising:
a step of loading a wafer ring holder holding the dicing tape to which the die is attached;
picking up the die from the dicing tape;
placing the picked-up die on the substrate;
A method of manufacturing a semiconductor device comprising:

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